Is it forbidden to use game cracks and serials for non-free programs? And what is the ruling if all computer programs used are in this manner, along with the necessity of using them?

It is impermissible, according to Islamic law, to use protected software and pirate it by any means whatsoever. This is because it constitutes an infringement on people's rights without just cause. One must promptly remove pirated software from their device and refrain from using it in the future. Necessity is not considered a legitimate justification for making people's property permissible.